Lattice Statistics and Dynamics within Cluster Variation Method

Abstract

The conventional Cluster Variation Method (CVM) does not explicitly consider both lattice vibration and local lattice relaxation effects. As discussed in the previous studies, these de ciencies result in overestimation of order-disorder transformation temperatures for the Cu-Au phase diagram. In the present paper, we propose modi ed CVM which explicitly takes both the effects mentioned above into account. By employing the present modi ed CVM, we evaluated both lattice vibration and local lattice relaxation effects, and estimated free energy of mixing for Cu-Au disordered phase at a nite temperature.

Pd–H and Ni–H phase diagrams using cluster variation method and Monte Carlo simulation

“…MC simulation allows to identify the atom positions of the ground-state and the CVM improves the MC calculation time providing integration constants. Our model could be improved by taking into account the effect of lattice vibration and distortion [55] in order to improve the accuracy on the DFT calculated energies. The effects of the important volume expansion on the atomic interactions could also be considered.…”